John Coletti/Getty Images(COLD SPRING, Minn.) -- As school districts across the country grapple with ideas to better protect students after a gunman killed 26 people at a Connecticut elementary school in December, a school system in Minnesota is stocking classrooms with bulletproof whiteboards to guard against possible future shootings.

The Rocori School District in Cold Spring, Minn., recently obtained nearly 200 of the 18-by-20-inch boards to be a last line of defense in the event of a classroom shooting like the one at Sandy Hook Elementary School in Newtown, Conn.

The district is the first in Minnesota to adopt the bulletproof whiteboards, but they're already in use in certain schools in California, Maryland and Pennsylvania.

According to the board's manufacturer, it is designed to cover a head and torso, and is capable of absorbing several magazines of ammunition from a handgun or shotgun "without ricochet or injury."

"It really is, from our perspective, another layer of security and protection and safety for the school district," Rocori School District Superintendent Scott Staska told ABC News. "Sandy Hook caused us as a district to go back and look at all the things we were doing, plus more that we can do to be proactive and make sure that we are as safe a school as possible."

Staska said the board is an effective shield because, in addition to being bulletproof, it provides an intruder with a different target to shoot at.

"If you're in the direct line of fire, statistically, 95 percent of shooters, if you give the shooter a target, that's probably what they are going to aim at, as opposed to anything else," he said.

The boards are made from a material called dyneema by Maryland-based armor systems manufacturer Hardwire LLC, which has provided armor to U.S. military vehicles in Iraq and Afghanistan in addition to law enforcement SWAT teams.

"It's a last line of defense," Hardwire spokeswoman Emily Heinauer told ABC News. "After the Sandy Hook shootings we thought, 'What can we do to help solve this problem?'"

Children threatened by a shooter could run behind a teacher wielding the white board, Heinauer said.

"It's a layer of protection to be used between the teacher and the shooter to buy time for law enforcement," she said.

She added that one of the benefits of the board is that it blends right in with the school environment, which is important to preventing negative psychological effects among young children, who may otherwise be frightened by a more prominent bulletproof shield in their midst.

According to Staska, demonstrations of the board in action have proven effective.

"The [police] chief demonstrated the board," he said. "He took a board out with his officers and fired rounds at them, with different types of weapons and distances. They could never really damage the integrity of the board."